The invention relates, generally, to a support system for a radiation system, and more particularly, to a support system for an x-ray source.
In medical radiological diagnostics, x-ray systems typically have an x-ray source, which may be disposed above a patient bed or above the patient. The patient bed may also be a cot, a table top, or gurney. Below the patient bed, on which the patient is placed, or behind the patient, an x-ray detector may be provided for recording x-rays that have penetrated or passed through the patient. The x-ray source may be mounted so as to be movable in all directions in space, i.e. in three dimensions. As such, the x-ray source can be used in versatile irradiation angles and positions, for instance with x-rays passing through the patient vertically or horizontally. To that end, the x-ray source may be mounted on the ceiling of an examination room using a ceiling holder. The x-ray source may also be mounted to a moveable x-ray system platform. The ceiling holder may be designed such that the x-ray source is adjustable in all three directions in space, so that desirable regions of the patient's body to be examined can be x-rayed. The ceiling holder is also rotatable, so that desirable directional angles can be achieved.
First, the three-dimensional movability of the x-ray source may be satisfied by providing that the ceiling holder is at least adjustable vertically. As such, the ceiling holder may have a mounting device or retaining device, having a telescoping mechanism. Second, the x-ray source may be secured to the mounting device or the telescoping mechanism via a support arm or support member of the ceiling holder. The support arm may be rotatable about the vertical axis of the mounting device, and the x-ray source is rotatable on the support arm about a horizontal axis. In addition, the mounting device can be secured to the ceiling of the examination room via a rail system, to allow for a horizontally desirable adjustment along an entire length of the patient bed.
Since the x-ray source may be substantially heavy or bulky, a plurality of the parts defining the ceiling holder may be dimensioned so as to be suitably massive. As such, considerable space may be taken up by a substantially bulky x-ray source and ceiling holder assembly. Moreover, mechanisms for supporting vertical motions of the x-ray source, in particular, may be provided so that an operator or user need not hold or lift the entire weight of the x-ray source along with the support arm and the mounting device. For supporting vertical motions, weight compensating devices, such as counterweights connected by cable, and under some circumstances involving even motors, are therefore provided. To improve a manual adjustability of the x-ray source, stable handles may also be provided, to facilitate, for instance, for the operator aiming of the x-ray source at body parts of the patient that are to be examined. All these mechanisms and components may contribute to a considerable spatial requirement of the overall x-ray system.
For a patient, to be examined, to experience a psychologically more favorable examination, the x-ray system in and under which he has to be placed may not be overly and oppressively massive. In addition, it is quite generally an advantage if the parts of the x-ray system are designed to be as space-saving as possible.
One possible way of increasing an available free space inside the x-ray system, for instance between the patient bed and the x-ray source together with the ceiling holder, is to design the support arm in such a way that the x-ray source can be moved upward as far as possible toward the ceiling of the room together with the mounting device. This design may increase the amount of free space between the patient bed and the moved up or raised x-ray source, and both the operator and the patient have more freedom of motion for placing and positioning of the patient. To achieve this design, the support arm may be given a shape that may be bent at a right angle as markedly upward as possible. As a result, an underside of the mounting device or of the support arm may form a lower edge of the entire assembly comprising the ceiling holder and the x-ray source, while vice versa the x-ray source may protrude no farther downward vertically than the ceiling holder. The vertical free space may then be limited at a top only by a maximum adjustability of the mounting device.
Now, however, for radiological examination of a patient, the x-ray source must be moved as close as possible to the patient, depending on the x-ray examination image or view to be taken. Typically, x-ray sources have so-called multileaf diaphragms (collimators), which can be moved to where they nearly touch the patient and thus predetermine a minimum spacing between the patient and the radiation generator. When x-ray examinations are made with such close spacing, all the edges of the ceiling holder may prove to be problematic or interfering, because they could come into contact with the patient. They can not only impair free movability but also hinder the minimum spacing between the x-ray source and the patient, if the patient is in the way of their motion or could even bump against them.
To avoid such problematic ceiling holder edges near the patient, the pronounced or exaggerated upward right-angle bend of the support arm may prove to be counterproductive. Instead and on the contrary, a substantially right-angle bend of the support arm in the downward direction may be necessary, so that the underside of the x-ray source may form the lower edge of the entire x-ray system. The movability of the x-ray source in an immediate vicinity of the patient to be examined is then restricted solely by the lower edge of the x-ray source.
A markedly downward right-angle bend of the support arm, however, may prove to be a hindrance to the above-explained upward adjustability of the x-ray system, which should be as great as possible, since the lower edge of the x-ray source is always located below the ceiling holder that is moved maximally upward and thus reduces a height of the room that remains available.
The support arms or members of conventional ceiling holders for x-ray systems have either a substantially upward right-angle bend or downward right-angle bend. Thus, in conventional ceiling holders, either a disadvantage of restricted upward adjustability and hence restricted vertical free space, or a disadvantage of pronounced problematic or interfering lower edges near the patient was accepted and incorporated into the design of the x-ray system.